Saturday, 17 September 2016

Deploying Homer with Puppet

Fan of Homer? So am I, and as sometimes happens I'm a fan who could join the team!

If despite the title of this post you're still reading, then it's a good sign and we can move on.

Homer is a vast project that aims to provide a tool, with a GUI, to correlate all the signalling, RTCP stats, events, logs in your RTC network. It focuses heavily on SIP, for historical reasons, but it's also an extendible framework to store other types of signalling, correlate data, and compute statistics. People browsing their github account are often heard saying "Do they have this too? And this? Wow!".

It is compatible off the shelf with common applications like Kamailio, opensips, FreeSWITCH, Asterisk, so if you're into VoIP, adding Homer to your platform is as easy as installing it and telling your apps where to send their data. There are also standalone tools like captagent, nodejs apps to parse and collect specific logs, to be associated with the related signalling, and a plethora of libraries, including a C one.

Anyway the topic is extremely vast and you can find a lot (a lot) of information on the sipcapture website.

Lately I've been working on Homer deployments using Puppet, a Configuration Management tool, so I wanted to share the experience, and as a result you can find a Puppet module in the homer-puppet repo. In fact this is re-written from scratch from previous experiences and focusing on debian/Ubuntu. Specific need on other distributions can be addressed without much effort, so anybody deploying their infrastructure with Puppet and using Homer is encouraged to look at this work and provide feedback and questions.

Homer can be installed with a well tested homer-installer and through Docker containers, so this work just adds to the deployment opportunities, but as usual in this field, what fits for an organisation may not fit for another.

The approach is quite flexible. Most of the data has a default value so the minimum amount of data to be passed to the module - which of course can be done via hiera - is very limited and aims to allow people to configure a new system in minutes.

Homer has 4 main components: the DB of course, kamailio or opensips to collect data from the apps, a web server for the GUI (homer-ui) and an API for the queries (homer-api). With homer-puppet you can git checkout the versions you need for homer-ui and homer-api and just launch puppet apply (standalone mode) to have everything installed and configured.

There is a default kamailio.cfg for storing data and providing stats, but that can be customised to your needs (see the modules/homer/files/kamailio folder inside the Puppet module).

Templates are used for the files containing variable elements (namely, mysql and admin credentials, and a few more).

I'm working on a version that instead of installing the components directly on the target host is designed to manage Docker containers (one for kamailio, one for the web part), through Docker Compose. There are many moving parts and while it fits well in a system that already includes a private Docker registry, it's trickier to "sanitise" and share. But I'm getting there.